Anthony Head, back in a British-made TV drama for the first time in more than four years, plays a suspected serial killer in the latest Silent Witness story, "Two Below Zero."

"I play Henry, a man with no morals and no ethics whatsoever," says the 45-year-old actor. "He's always had an eye for girls very much younger than himself, so, when the bodies of two teenage girls are discovered, he becomes a likely suspect."

Anthony enjoyed working on the tense two-parter, not only because it offered him a meaty role but because it meant being able to spend time with his family. That is a rarity for him these days, now that he is an international TV star.

He co-stars with Sarah Michelle Gellar in the hit US sci-fi series Buffy the Vampire Slayer, in which he plays English librarian Rupert Giles.

The show is filmed in Los Angeles, which means the London-born actor spends eight months of the year away from his long-time partner, Sarah, and their daughters, Emily, 11, and Daisy, nine. They live at the family home near Bath and remain stoically resilient as he pursues his career on the other side of the Atlantic.

Anthony says: "Going to America was a hard decision and I sometimes wonder if it's fair to ask Sarah to be a single mother for most of the year - which is effectively what she is - for the sake of my career." But she's a remarkable lady and knows it's too good an opportunity for me to miss. And the girls tell me I mustn't even think about giving up on Buffy. They all know it's not going to last forever, although I can see the show continuing for another couple of years at least.

"I get back home every four or five weeks and we talk on the phone every day. The plan always was to reinvent myself back in Britain, which is what I'm doing now.

"Silent Witness was the perfect job. We filmed in Hertfordshire, so I was able to commute each day and there was plenty of time off to enjoy things with the family."

He last worked in British TV, again for the BBC, playing a magician in the first series of Jonathan Creek but, by the time he got the call for the second series he was already committed to Buffy.

Earlier, his career could have taken an awful dive. Once the "will they, won't they" Gold Blend ads with Sharon Maughan had run their course, Anthony could get only theatre work. Television and film producers didn't want to know.

But he was known on US TV where his ads had been aired under the brand name Taster's Choice. They got him noticed and an American agent.

And it has made Anthony Stewart Head a recognisable face around the globe, thanks to his role of school librarian Robert Giles.

It's a far cry from the days when he was one half of the couple in the first Gold Blend adverts that gripped the nation with their "will they or won't they" storylines.

Viewers could well be forgiven for forgetting about the dashing 47-year-old actor, who in those days was plain old Tony Head.

After the end of the commercials, TV work dried up and he went to live in Santa Monica, near Los Angeles, in search of success.

First, he appeared in the sci-fi series VR5 and then Buffy, with Sarah Michelle Gellar, came his way.

But his success in America has been hard won. Head has to split his time between work in Hollywood and trips back home whenever he has a short break to see his two children.

"I try and make it for about six days a month," he says. "Anything less would be just too disruptive.

"I have a nice apartment in Santa Monica but my girls have to share a room when they visit, which doesn't go down too well. They put up with it, though, because they get to go to Universal Studios and Disneyland."

Head believes that it was his success in the Gold Blend adverts that led to his exile from Britain.

"I was earning a decent crust off the commercials, so I was able to pick and choose. But if you are not in the public eye your profile diminishes. That's when I decided to try the States."

It was a tough ride to begin with, until wife Sarah gave her husband a piece of advice.

"She told me to stop moaning, and do something positive, like taking acting classes. I bristled a bit at that, I had been to drama school after all."

But he bit the bullet and signed up with Milton Katzelas, whose pupils have included Michelle Pfeiffer.

"His teaching is about attitude to life and he is held in huge regard. When he walks into a class everyone applauds, now that's very West Coast!"